Sports programming used to be a license to print money.

Even as the rest of the television business was showing signs of strain, with younger users cutting the cable cord or even avoiding cable altogether, sports seemed like a bastion of safety for media companies—the one reliable thing for which users would always be willing to pay.

But cracks are starting to appear in the foundation of that assumption.

Some of the biggest cracks so far have shown up at ESPN, the multi-billion dollar broadcasting behemoth controlling access to a huge swath of programming from almost every major sports franchise from the National Football League to Major League Baseball. Shares of Disney DIS 0.89% , the media conglomerate that owns ESPN, have been under pressure for much of the past year— primarily because of concerns about the sports network.

As growing numbers of TV watchers either cut the cord entirely or opt for what cable providers like to call “skinny bundles,” ESPN’s iron grip on viewers and subscribers is being questioned in a way it never has in the past. That’s a big deal for Disney shareholders as the sports network makes up a huge proportion of the Mouse House’s profits.

ESPN president John Skipper maintains that cord-cutting isn’t as big a deal as some industry critics make it out to be, insisting the network is having some success retaining subscribers by being part of skinny bundles, such as Dish Network’s SlingTV package. ESPN has also hinted that it might decide to go over-the-top with its own streaming service at some point.

Despite this bravado, however, the fact remains that ESPN has lost about seven million subscribers since 2013. Yet at the same time, ESPN has spent billions of dollars locking up the rights to various major sporting events.

Other cracks in the foundation of the sports programming kingdom are showing up on a local level, evident in negotiations between individual channels and cable providers like Comcast. As the Wall Street Journal notes in a recent piece, New York Yankees games have been blacked out on Comcast since November because of an ongoing battle over licensing fees between the cable company and the Yankees Entertainment and Sports Network (YES), a subsidiary of 21st Century Fox and the entity distributing Yankees game broadcasts.

In addition to the fight between Comcast and YES over what the sports channel wants to charge for carriage on Comcast, there are other regional fights going on involving pay TV providers, such as Direct TV and SportsNet LA, the network that broadcasts Los Angeles Dodgers games. Time Warner Cable, which distributes SportsNet LA, recently agreed to cut its fees by 30%.

The problem for both ESPN and smaller players like YES is that they have spent heavily over the past few years to lock up the rights to sports programming because doing so used to be a license to print money.

But as cord-cutting has eaten into the traditional grip that sports had on the TV business, the assumptions behind those valuations are coming into question. “I believe that finally sports TV is in crisis mode,” Jimmy Schaeffler, head of media and telecom consultancy Carmel Group, told the Journal.

As the Journal story points out, YES signed a deal with the Yankees to lock up TV rights for 30 years at a cost of about $1.5 billion. Last year, 21st Century Fox increased its ownership of the network from 49% to 80% in a deal that valued the network at almost $4 billion. That may have looked like a great bargain at the time, but it’s not clear that YES or any of its sports programming brethren are worth as much as they appeared to be.

The great unbundling of traditional broadcast television has implications for all kinds of content, including TV shows and movies. But nothing else has had quite the same hold on consumers as sports programming, and the unwinding of that massive, decades-long value chain is going to cause a lot more pain before it is finished.

Article Written By: Mathew Ingram